Field of the Disclosure
The present disclosure relates to a technique for accurately determining a type of a recording material and controlling an image forming condition according to the determination result.
Description of the Related Art
Conventionally, there has been an image forming apparatus such as a copying machine or a printer including a sensor for determining a type of a recording material. Such an image forming apparatus automatically determines a type of a recording material and controls a transfer condition (e.g., a transfer voltage or a conveyance speed of a recording material in a transfer period) or a fixing condition (e.g., a fixing temperature or a conveyance speed of a recording material in a fixing period) according to the determination result.
Japanese Patent Application Laid-Open No. 2009-029622 discusses an image forming apparatus including a recording material determination unit that determines a type of a recording material by emitting light to the recording material and capturing the light reflected on the recording material as an image through a complementary metal oxide semiconductor (CMOS) sensor. In this image forming apparatus, a transfer voltage, a fixing temperature, and a conveyance speed of the recording material are controlled according to the type of the recording material determined by the recording material determination unit. With this configuration, an image of high quality can be formed on the recording material.
However, because of an influence of production variation arising in recording materials, similar detection results may be acquired, as detection results of the sensor, from the recording materials of different types. In such a case, as it is difficult to accurately determine a type of the recording material, the recording material may be erroneously determined as a recording material of a different type, and an image is formed under the image forming condition not suitable for the recording material of that type. Thus, this may result in degradation in the image quality. Although the control method described in Japanese Patent Application Laid-Open No. 2009-029622 has sufficiently realized the image quality desired in those days, it is desirable to further improve the accuracy for determining the type of the recording material in order to realize the image quality required in these days.